I have a map saved as MrSid file which when loaded in QGIS displays as a southern hemisphere location despite being in the UK. When looking at the .sdw file the northing is positive but in QGIS it shows as negative. Adding a minus sign to the northing in Notepad and resaving still displays it as a negative value. How can I correct this?

  • What CRS is assigned to the layer reported by Rightclick on the layer name -> Properties, CRS tab? – AndreJ Nov 18 '14 at 17:02
  • Thanks AndreJ, The answer is USER:100002 - * Generated CRS (+proj=tmerc +lat_0=0.999601272 +lon_0=0.999601272 +k=0.999601272 +x_0=0.999601272 +y_0=0.999601272 +ellps=airy +towgs84=446.448,-125.157,542.06,0.1502,0.247,0.8421,-20.4894 +units=m +no_defs). Now I find I can change the CRS to OSGB 1936 / British National Grid and use the map in a project but cannot save it as a Gtiff with the OSGB CRS. Still there is progress for which I am grateful. – John Webber Nov 20 '14 at 16:35

The CRS data you report looks rather broken, with the k factor value stored in other parameters where it does not belong.

For reprojecting rasters, you have to use Raster-> Projections -> Warp. Reprojection using Save As only works for vector data.

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